Expression device for sound-producing instruments



w. A. JOHNSON.

EXPRESSION DEVICE FOR SOUND PRODUCING INSTRUMENTS. APPLlCATiON FILED JAN. 17, 1917.

1,408,514. Patented M11922;

2 SHEETS-SHEET 1.-

if .6? if INVEI ITOR Wl'l/iam 7 T07 44 A TTORNEY W. 'A. JOHNSON. EXPRESSION DEVICE FOR SOUND PRODUCING INSTRUMENTS.

APPLICATION men JAN- H. 1917.

Patented Mar. 7, 1922.v

2 SHEETS-SHEET 2;

,4 TTOR/VEY WILLIAM A. EOHNESUN, 03? "5. 01 KERS, NEW YORK.

EXPRESSION DEVICE FOR SOUND-PRODUCING INSTRUMENTS.

I Specification of Letters Patent.

Patented Mar. 7, 1922.

Application filed January 17, 1917. Serial No. 142,832.

To all whom ii'mag concern:

Be it known that I, WILLIAM :1. JOHNSON, a citizen of the Unlted States, and a resident of Yonkers, county of Westcheste'r, and

State of New York, have inventcdcertain new and useful Improvements in itizpression Devices for Sound-Producing Instruments of which the following is a specification, reference being had :to the accompanying drawings, forming a part thereof.

My invention relates to talking machines, phonographs and other automatic musical instruments, and has special reference to devices for'governing the expression of instruments of this character.

One object of my invention isto provide an expression controlling device for the aforesaid purpose that shall, not only be promptly responsive to the will of the operator, butalso have a particularly direct effect upon the reproducer itself rather than upon the passage through which the sound is transmitted after it is produced.

Another object is to provide a simple and compact structure for acting upon the mechanical connection between the needle or stylus and the reproducer, whereby the amplitudeof the vibrations transmitted from the record to the diaphragm of the reproducer, may be directly under the control of the operator. V

In order that my invention may be thor oughly understood I will now proceed to describe the same in the following specification, and then point out the novel features thereofin appended claims.

My invention may be embodied in-various more or less dissimilar structures and those included in the drawings areintended only for purposes of illustration and to enable anyone skilled in this art to practice the in-' vention.

Referring to the drawings,

Figure 1 is a transverse sectional elevation ofa reproducerequipped with an expression controlling means which constitutes one embodiment of my invention.

Figure 2 is a front elevation of the same mechanism. y

Figures 3 and 4 are sectional plan views taken on the. lines 7-7 and 8 -8 respectively of Figure 1. Figures 5 and 6 are views corresponding to Figures 1 and 2, showing still another modification of my invention.

Figure 7 is a sectional plan view drawn to alarger scale and taken on the line 1111 of Figure 5.

Another modification of my invention is shown in Figure 8 which corresponds to Figure 2.

Referring first to Figures 1, 2, 3, and 4 in which like parts are designated by the same reference characters, the structure here shown comprises a diaphragm 15 which is supported in the usual manner and forms a part of the sound box or reproducer which is designated by 16 and has a frame 17, a socket 18, and a clamping ring 19. 4O designates a stylus lever which is pivoted at 41 on a projection 4270f the clamping ring 19. The lever 40 has a spring 43 which is adjustably connected to the frame 17 by a screw 44 and tends to hold the lever in a neutral position. A lever 45 is pivoted at 46 on the opposite side of the ring 19 from the pivot 41 and extends through the axis of the diaphragm 15 and is connected thereto by a link 47 which is affixed to the diaphragm at 48.

- The arrangement of parts is such that the lever 45 and the stylus lever 40 are substan-' tially parallel and the two are interconnected by a movable link 49. The posit on of the link may be adjusted, together with an arm 50 which is secured thereto, by means I of a piston 51 and a cylinder52. The air pressure in the cylinder back of the piston is varied at the will of the operator who holds a bulb or plunger (not shown) connected tothe cylinder by a flexible tube 53. It is to be understood that a, spring like that shown at 77,- Fig. 6, may be used to oppose the action of the air pressure.

The arrangement of the fiat spring 43 and its adjusting screw 44 is clearly shown in the sectional plan view of Figure 3 and the link 49 is hown on a larger scale in Figure 4. As here shown it is provided with mortises 54 which are adapted to receive the lever arms 40 and 45. notches or grooves 55 forming sockets to receive a binding spring 56. This spring, as shown in Figure 4, has the form of a yoke and presses the lever arms 40 and 45 into the bottom of the mortises 50 and 54. The

The mortises have bulb or plunger in the hand arrangement is such as to permit the link 49 to slide up and down in response to the action of the piston 51 and yet perform the function of a rigid link interconnecting the two levers.

The amplitude of the vibrations transmitted from the stylus lever 40 through the lever 45 to the diaphragm 15, is obviously varied by the position of the link which, as already explained, is directly under control of the operator. i

In the structures shown in Figures 5, 6 and 7 a stylus lever is affixed to the diaphragm 15 at 61 with its other end'yieldably supported by a spring 61 and has grooves 62 which. extend longitudinally as shown in Figures 5 and 7. A stationary guide arm 63 is aiiixed to the clamping ring 19 and is provided with grooves 64 which correspond with the grooves 62. A sliding block composed of two side plates, 65 is mounted on the stationary arm 63 and is pivotally connected to the arm 60 by a pair of pivot balls 66 which are disposed in sockets 67 in the plates 65.- The plates have sockets 68 in which balls 69 are mounted to correspond with the pivot balls 66 and engage the guide slots6 i in the fixed arm 63.

The plates are pressed together and are connected to the link 70 by a pin 70 and springs 70" thereon as shown in Figure 7.

The arrangement of parts is such-that the arms 63 and 60 are substantially parallel and are joined by the slidingblock or link 65 which constitutes an adjustable pivot for the stylus lever 60. V I

The stylus lever 60 vibrates according to the oscillations caused by the record. Spring 61 yields to these vibrations freely. Assuming for the purpose of explanation a vibration that carries the lower end of lever 60 in a counter clockwise direction, see Fig. 5. the upper end of lever 60 presses diaphragm 15 to the left, the pivot balls 66 serving as a fulcrum, and lever 60 being a lever of the first class. The fulcrum may be readily moved, and the ratio of leverage changed, by moving link 70 as previously described, and thus adjusting the position of the slidableblock composed of plates 65, 65. The change in ratio produces a change in the amplitude of movement of diaphragm 15 with a given extent of movement of stylus lever 60. i

The adjustment of the block and of the pivot is effected by a link 70 which is suspended from an arm 71. This arm is adjustably mounted on a pistonrod 72 which may be guided in a stationary support 73 as shown in Figure 6. A pneumatic cylinder 74: is connected by a flexible tube 75 to some suitable means for varying the air pressure within the cylinder such as, for example, a of the operator, and has a p1ston76 to which the rod 72 is connected. When the air pressure in the cylinder 74 is suflicient, the arm 71 is raised in opposition to gravity'or a spring such as 77 and elevates the block 65. that the pivot of the stylus lever 60 is moved closer to the point of attachment between the lever and the diaphragm. Consequently the amplitude of the vibrations imparted to the diaphragm are reduced. The opposite movement of the pivot has the opposite effeet and it is evident that the amplitude of the vibrations may be controlled to control the expression as desired.

Instead of the guide-63 a T-shaped guide arm 80 may be employed as shown in Figure 8, permitting the cylinder 74 to be dis-- posed directly above the block 65 and the piston 76 connected to it by a yoke 81 and a pair of'links 82 which take the place of the link 7 O. The result desired is the same, viz., the movement of the block 65 to effect an adjustment of the pivot for the stylus lever 60.

Attention is directed to the fact that my invention may be embodied in a simpleand compact mechanism and while it is highly responsive to the touch of the operator it The result is nevertheless is applied in a particularly direct manner, so that there is no appreciable time elem'entintervening. V

The structure illustrated may be modified in various ways within the spirit and scope of my invention and I intend that only such limitations be imposed as are indicated in the appended claims.

What I claim is:

1. In an automatic musical instrument,

the combination with a sound produeingele ment, an element adapted to be vibrated by contact with a record, and slidable means controlling the ratio of amplitudes of vibrations of the record vibrated element relative to the sound producing element, of expres' sion controlling means movable duringthe operation of the device adapted to move said slidable means variable at the will of the operator.

2. The combination with a musical instru 7 sound producing element.

3. In combination with a sound producing I element, a stylus lever, and means operable during production of sound for adjusting the pivot of the stylus lever to vary the amplitude of the vibrations imparted to'the sound producing element to controlthe ex- 6 pression of the device. a

A. In combination with a sound producing diaphragm, a stylus lever secured thereto at one end having a yielding support near its opposite end, and an adjustable pivot block supported independently of the stylus lever, said block having a pivotal connection with the stylus lever and adapted to determine the amplitude of the vibrations between the stylus and the diaphragm ends of the lever.

5. A musical instrument comprising a diaphragm, a stylus lever attached to the dia phragm at one end, an adjustable pivot for the lever, and means for positively shifting the same longitudinally of the lever to vary the amplitude of the vibrations of the lever.

6. A musical instrument comprising a diaphragm, a stylus lever attached to the diaphragm at one end, an adjustable pivot for the lever, a relatively stationary guide for said pivot extending substantially longitudinally of the lever and means for shifting the lever pivot on said guide.

7. A musical instrument comprising a diaphragm, a stylus lever attached to the diaphragm at one end, yielding means for supporting the stylus lever near the opposite end, a relatively stationary guide substantially parallel to the stylus lever, a block movably mounted on the guide and consti tuting an adjustable pivot for the stylus lever.

8. A musical instrument comprising a diaphragm, a stylus lever attached to the diaphragm at one end, yielding means for sup. porting the stylus lever near the opposite end, a relatively stationary guide substantially parallel to the stylus lever, a block movably mounted on the guide and constituting an adjust-able pivot for the stylus lever, and means for shifting the position of said adjustable pivot on the relatively stationary guide during the operation of the device.

9. In combination with a diaphragm, a stylus, mechanical connections between said stylus and the diaphragm for transmitting vibrations of the stylus to the diaphragm, and manually controlled means for varying the relations of said connections to vary the amplitude of the transmitted vibrations during the operation of the device.

In witness whereof, I have hereunto set my hand this 11 day ofJanua'ry, 1917.

WILLIAM A. JOHNSON. 

